Siglent Technologies SPD3303X-E Triple Output Power Supply

Product: Siglent SPD3303X-E Programmable DC Power SupplyUse: for work lab setup at my house (work from home)Purchased: July 2022 (2-3 months of usage at the time of this review)Background/Usage: I am an engineer with 30+ years of post graduate experience with a focus of 25+ years in the design and development of medical imaging equipment. This is the 3rd piece of Siglent equipment I own, along with the Siglent SDG6022X Arbitrary Waveform Generator and the Siglent SDS2204X Plus Digital Storage Oscilloscope (many additional options purchased).My overall impression is that I like this power supply. I have been exposed to and used many other manufacture equipment from many of the top brands. Since I purchased this using my "dime", I tend to balance form, function, quality, price and several other factors.Value: I could have spent a lot less and gotten a lot less features and quality. For me, quality was a heavier factor that you just are not going to get with those sub $100 supplies.Quality: The build quality is very good. A bit noisier than what I personally like, however, not as noisy as some very expensive and most cheap counter parts. With this being in a lab bench setup with several other pieces of equipment, noise is noise. Screen display is sufficient for what is needed, showing what one needs to see. Buttons and knobs are more than sufficient, decent quality. My one "ding" (CON) is the banana plugs feel a bit cheaper than everything else on this piece of equipment and are non-standard size for a BNC dual banana plug adapter. This is a big oversight on Siglent's part and a common point of complaint. I overlook this and can easily work around it.Features: For the value, this is feature rich. I know the specs say this is 3 output, and technically it is... however, only 2 are IMHO independently controlled, those being the 32 volt @ 3.2 amp outputs. The 3rd one is a selectable 2.5/3.3/5.0 volts @ 3.2 amp output. So yes, technically 3. I do like and use the 3.3 volt or 5.0 volt output for small prototype boards. Adding a 12.0 volt selection would have been a win IMHO... but so be it. The 2 independent programmable outputs can be put into series for up to a 60 volt @ 6.4 amp max output. Something I won't need but nice. I utilize the minimum resolution of 1 mV and 1 mA setting ability. Although many may not need this fine resolution, it is very necessary in my line of work dealing with very small signals.I am happy with this supply and would recommend it.

There are some good reviews of the features and performance of this supply, so I will just mention that Siglent appears to now be shipping a new version of hardware (and firmware) with the SPD3303X-E. Presumably this corrects the issues reported in some recent reviews with DOA or short-lived units that reboot continuously. I just received a new unit and the calibration date is Dec. 2023. The unit shows it has V6.2 hardware and a firmware release that is not even available for download yet on Siglent's website (as of March 2024). So I am going to ASSUME based on this that the issues reported with the older versions has been fixed. So far the unit has operated flawlessly, and the two main (32V) outputs are accurate to better than the stated resolution. The third output is very limited and I don't really see myself using it, but if you need a logic source it should work for that. The UI is perhaps a little unusual but in my opinion, it's very simple to learn and operate. I've used the series-output function to power 48V devices and it works well for that (note that it is limited to 60V in series, not the 64V that you might expect). I have not had a use for the parallel (higher current) function yet. I appreciate the variable-speed fan. With the outputs off and the unit powered on, the fan does not operate. It starts to spool up at around 30-40W of output, but it's not until you get above 50% of rated power that the fan noise becomes what I would describe as noticeable. This is replacing an older single-output linear supply that had very noticeable fan noise even at idle output, so I can live with the fan on this one. I haven't done anything fancy with it yet like control it remotely or save/recall setups, and not sure I'll need to as I'm not an engineer, I'm a telecom technician. It's pretty heavy, but all good linear supplies are. The leads, while decent and tight-fitting in the sockets, are only 1M in length so you'll need to be closer to the supply to use them, or you can do what I did and buy some 5- or 6-foot test leads on Amazon (they're out there). So far I'm pleased with this unit.

I have used mine for 2.5 years now, powered it up over 250 times, and it is still like brand new. Let's start with the most important feature: voltage accuracy. I have a couple of Siglent SDMs, and they show the precise calibration of the voltage settings to be less than 0.016 % from 1.0 V to 30.0 V !! , with little or no drift. The residual AC must be very low, (the minimum I can measure is 0.5mV with SDM bandwidth ~600KHz ). I have not tested it yet under maximum loads. The Ethernet and USB interfaces work as expected and I was able to easily create several Python programs to run it thru its paces under Linux. The Windows software did not work and reluctant to install the bloated NI-VISA. The 10mA precision ammeter is a tiny bit disappointing, and the 'non-E' version of this supply with a 1mA display is $150 more! If you need to monitor small loads precisely you'll need to add an SDM to the measurement loop. Two years ago, I did a firmware update to improve the network capabilities and was forced to get the Windows software working. I had a bit of trouble and the Support Engineers were extremely helpful. There are several app notes and videos available. The firmware seems very stable now. The delivery was great, very good packaging, and reliability is good too. ...very happy with it.